There is still more than a year to go before the Olympic Games light up London’s sky, but already, enthusiastic crowds can be found peering into the largest construction site in Europe. The city has come down with a widespread, and highly contagious, case of Olympic fever.

One recent chilly weekday, some 100 people (mostly British) gathered outside the Bromley-by-Bow Tube station in East London for a certified Blue Badge Tourist Guide-led walking tour along the banks of the River Lee to the Olympic site. Leaving at 11 am every day, rain or shine; the tour started more than a year ago and will continue after the Games are over. When the group reached the Greenway (the only area of the official site open to the public), they were joined by even more tours and individuals who had come to see whatever they could of the spot where sport history will be, and already is being, made.

On 27 July 2012, when the torch is lit inside the main stadium, London will become the only three-time host of the event since the Olympics were revitalized in 1896. But this year promises more spectacle than their last two outings. In 1948, the heavily shelled city ended a 12-year hiatus imposed by World War II, but erected no new buildings for events or athlete accommodations. The "Austerity Games", as they were dubbed, came 40 years after the eruption of Mt Vesuvius scuttled Italy's hosting plans and the 1908 games were relocated (relatively last minute) to the West London neighborhood of White City, where the main campus of the BBC now resides.

Just under 100 years later, London routed Paris, Madrid, Moscow and New York to grab the upcoming Games, and it so far seems a well-deserved win. Unlike the last two summer Olympiads (Athens in 2004 and Beijing in 2008), and the recent disastrously unprepared Commonwealth Games in Delhi last year, the 2012 Olympics are currently - astonishingly - under budget and ahead of schedule.

London's Olympic site, which sits on an island connected by five bridges, is in the industrial neighbourhood of Stratford, a diverse but impoverished part of town. Once the city's centre for milling and shipping, and home to a heavily polluted river, Stratford was a counter-intuitively attractive facet of the city's bid. The Olympic Committee puts a premium on sites that will benefit from post-Games revitalization, and the plans for Stratford are extensive. The Olympic park's future, an era known as Legacy, promises new (and affordable) housing, better public transportation, a clean river, 4,000 new trees (the first was planted by Her Majesty The Queen), the city's largest shopping mall, and the largest urban park to be built in Europe in the last 150 years. Of the 9.3 billion pounds being spent in new construction, 75 percent has been allocated to sustainability. To help combat rampant local unemployment, the Olympic Delivery Authority (ODA) hired 20 percent of their workers from East London, exceeding their promise of 15 percent.

To visit the emerging site, you do not need a guided tour. The Greenway's entrance is next to public transportation and offers a cozy café inside converted freight containers, serving soups, sandwiches and warming beverages. Large, detailed maps help visitors identify (and visualize) the buildings of the Olympic park.

The most prominent is the Olympics Stadium, a white bowl crowned with origami-like folds, which will host the Opening Ceremonies, team matches and track and field events. From the Greenway's view, the stadium obscures the hockey and handball venues but, looking right, a visitor can spot a portion of the brown Velodrome (nicknamed the Pringle for its resemblance to that brand of potato crisp); it is the most advanced cycling track ever built, and experts predict it will aid athletes in breaking world records. Then there is the square, cream-coloured windowless basketball arena whose exterior will be a canvas for a nightly lightshow by the folks who illuminate U2 rock concerts. Just to its right sits a small city of apartment buildings where the athletes will sleep and eat. In front of that Olympic village, a brick-red helix art installation-cum-viewing-tower by artist Anish Kapoor called "ArcelorMittal Orbit" is rising up (it is only a third complete). Finally, to the far right, in a building resembling a breaking wave, is the Aquatic Centre that will host all swimming and diving events.

After the Games, the hockey and basketball arenas will be recycled into other uses, or perhaps reassembled for the 2016 Games in Rio de Janeiro. The Olympic Stadium will be the new home of the West Ham United football club, and the Olympic Village will convert into at least 2,800 apartments and a new school for the arts. The Velodrome, Aquatics Centre and handball arenas will continue to function as venues for biking, swimming and other sports, but in Legacy, the general public can have a go at breaking world records in them.

Looking down on the Olympic site from the Greenway is electrifying for its scale and impending glory, but the distance from the venues is a disappointment. Fortunately the ODA offers weekend bus tours that bring you through the heart of the park and around the buildings. Some of the bus rides are narrated by a Blue Badge guides and it covers much of the same Olympic and local history as with the walking tour, but it is free and closer to the action. There are two catches to the bus tour: you need to book weeks in advance (the daily walking tour accommodates increasing visitors by splitting groups among multiple guides) and you can only do the tour once a year. Take it now and you can return just before the Games begin.

Long after we have forgotten the achievement of individual athletes, it is the host cities we remember for their Olympic success. In 2002, I visited what was then the future site of the 2008 Beijing Olympics, and it was nothing more than a dusty field with a small billboard. But the pride the city and its residents displayed in their preparations for the event was moving and rightly placed-Beijing pulled off a triumph of pageantry and civic achievement. At the conclusion of it, they handed the hosting duties over to London via a red double-decker bus carrying David Beckham that drove into the Bird's Nest stadium. From what I saw at the half-erected construction site and enthusiastic crowds in Stratford, London is on pace to give Beijing a run for its money.

How toTo book the ODA's weekend bus tour into the Olympic site, call +44 (0) 300-2012-001. For more information on the 2012 Olympics visit www.london2012.com. There are several private tour companies and many guides visiting the Greenway, but one of the largest is the daily walking tour described above by Tour Guides LTD, which can be booked at www.tourguides2012.co.uk and costs 9 pounds. To visit the site on your own, the entrance to the Greenway is just outside the Pudding Mill DLR station of the Underground.